Caustic alkali free oven cleaning composition

ABSTRACT

THIS APPLICATION CONCERNS NON-CAUSTIC ALKALI WATERBASED OVEN CLEANING COMPOSITIONS COMPRISING WATER, SOAP, INORGANIC CLEANER AND AN ENHANCER OF THE FORMULA   NH2CH2CH2CH-(OCH2CH2)N-OH   WHEREIN N IS A NUMBER FROM ABOUT 2 TO ABOUT 12. THE COMPOSITIONS MAY CONTAIN ADDITIONAL INGREDIENTS USEFUL IN OVEN CLEANERS SUCH AS THICKENING AGENTS, HUMECTANTS, ORGANIC SOLVENTS, FOAM STABILIZERS AND ABRASIVES. SPECIAL ATTENTION IS HEREIN DIRECTED TO AEROSOL SYSTEMS CONTAINING THE ABOVE-DESCRIBED COMPOSITIONS.

United States Patent 3,658,711 CAUSTIC ALKALI FREE OVEN CLEANING COMPOSITION Cromwell D. Mukai, Berkeley Heights, and Frank L.

Steckhahn, New Shrewsbury, N.J., assignors to American Home Products Corporation, New York, N.Y. No Drawing. Filed June 3, 1970, Ser. No. 43,246 Int. Cl. Clld 17/00 U.S. Cl. 252-90 8 Claims ABSTRACT on THE DISCLOSURE This application concerns non-caustic alkali waterbased oven cleaning compositions comprising water, soap, inorganic cleaner and an enhancer of the formula wherein n is a number from about 2 to about 12. The compositions may contain additional ingredients useful in oven cleaners such as thickening agents, humectants, organic solvents, foam stabilizers and abrasives. Special attention is herein directed to aerosol systems containing the above-described compositions.

This application relates to new and novel compositions for use in cleaning ovens and similar surfaces. More particularly, this invention concerns the above new and novel compositions which are composed of water, a soap, an inorganic cleaner, an enhancing agent and optional ingredients which are efficaciously present in oven cleaning compositions such as thickeners, foam builders, humectants, organic solvents, foam stabilizers and abrasives. Additionally, this invention is concerned with systems useful in containing and applying the above-described new and novel compositions. These systems include packages at room pressure used to contain the compositions for application such as with a cloth or brush and aerosol systems, both self-contained pressurized and pump activated, for application of the composition in the form of a foam or a spray.

Among the most distasteful of the necessary household tasks is that of cleaning the oven. Because of the deposit of grease, both fresh and baked on, and hard baked-on food spills, the job of oven cleaning becomes all but impossible. However, it is necessary to regularly clean an oven in order to prevent the buildup of deposits which prevent even heat distribution and mar the appearance of the modern home. In recent times, several types of products have appeared on the market which are intended to aid in the cleaning of dirty ovens. However, the active ingredient in the majority of these oven cleaners is a caustic alkali (i.e. potassium or sodium hydroxide), as exemplified in U.S. Pats. No. 3,031,408 and No. 3,031,- 409. Although caustic alkali provides an excellent oven cleaning composition, several inherent drawbacks are evident in its use. Caustic alkali is dangerous to the eyes and when used in the form of a pressurized aerosol, presents a great hazard to the sight of the user. Additionally, caustic alkali is irritating to the skin and generally requires the concurrent use of gloves to avoid undue dangers to the skin, relating to its use. The present invention has as its object the providing of oven cleaning compositions which are free of any caustic alkali and, therefore, are useable by the consumer with comparative safety.

Although some non-caustic alkali containing oven cleaning compositions are known, these known compositions each have drawbacks to their use. One type of non-caustic alkali containing oven cleaner relies for its cleaning properties on the use of high levels of organic solvents. Al-

though these solvents are suflicient to remove fresh grease present in an oven, they are of little or no benefit in removing the commonly occuring burnt-on grease. A second type of non-caustic alkali oven cleaner relies on certain primary, secondary and tertiary amines to provide the necessary cleaning ability, as exemplified in Republic of South Africa patent application No. 686,- 992. These compositions which rely on low molecular amines provide low levels of active cleaning power and fume when used in a hot oven, creating serious mal-odor problems. Such compositions are also exemplified in Auslegeschrift 1,263,963 of Mar. 21, 1968. It is, therefore, an object of this invention to provide water-based, non-caustic, alkali non-fuming over cleaner compositions of enhanced cleaning ability.

The enhanced, non-caustic, non-fuming oven cleaner compositions of the present invention are composed of water containing, by weight, from about 0.01% to about 2.00% of soap; from about 1.00% to about 15.00% of an inorganic cleaner; and from about 0.10% to about 40.00% of an enhancing agent of the formula:

wherein n is a number from 2 to about 12. These enhancing agents all possess terminal amino groups which have a vapor pressure less than .01 mm. Hg at 20 C. or a boiling point over 350 F.

More particularly, the compositions of the present inyention are composed of water (preferably over 60% of the final composition), containing, by weight, from about .05% to about 1.00% of a soap, from about 4.00% to about 10.00% of an inorganic cleaner; and from about 0.10% to about 40.00% of the enhancing agent. Of particular interest are the above-described compositions wherein the enhancing agent is present in the range of from about 0.5% to about 30.00%.

Additionally, the compositions of this invention may contain one or more additional substances useful in oven cleaning compositions, selected from the group consisting of thickening agents, humectants, organic solvents, foam stabilizers and abrasives. Particularly of interest are compositions wherein the above substances are present in the composition in the amount of from about 0.50% to about 1.5% of thickening agent, from about 5.00% to 25.00% of humectants, from about 5.00% to about 20.00% of organic solvent, from about 0.10% to about 1.00% of foam stabilizer and from about 0.10% to about 5.00% of abrasive.

The component ingredients of the above-described compositions are each selected to perform a particular function. Therefore, ingredients which would react with each other adversely or hinder their respective effectiveness are not selected. It is, of course, possible in certain instances to choose substances which demonstrate more than one useful property. The inorganic cleaners present in this invention are useful in aiding in the removal of the accumulated grime from oven walls. The inorganic cleaners (builders) are selected from the alkali metal or ammonium salts of substances such as carbonates, phosphates, borates and silicates. Of particular interest are sodium, potassium or ammonium carbonates, phosphates and silicates especially potassium carbonate, tripotassium phosphate, trisodium phosphate and tetrasodium pyrophosphate. The soap included in the compositions of this invention serve to aid in the removal of oven grime and to opacify the compositions. Illustrative of the soaps which may be used in the present invention are the well-known salts of fatty acids. These may include the Na, K, Li and ammonium or amine salts of myristic, palmitic, stearic, behinic, oleic, lauric, abietic, capric, caproic, caprylic, ricinoleic, linoleic, hydrogenated and dehydrogenated abietic acids, the surface active hydrolysis products of tallow, coconut oil, cottonseed oil, soybean oil, peanut oil, sesameoil, linseed oil, olive oil, corn oil, castor oil and the like. The enhancing agent serves to greatly enhance the activity of the other ingredients and under normal use conditions allows the removal of baked-on grease and food from ovens without the use of caustic alkali. The enhancing agent of particular interest is 2-[2-(3- aminopropoxy)ethoxy]ethanol Polyglycolamine H-163, Union Carbide).

Thickening agents are present in the composition to provide body to the composition, allowing it to remain in contact with the oven surface without running. Exemplary of useful thickening agents are colloidal magnesium aluminum silicate, alginates, carboxymethyl cellulose, carboxyethyl cellulose and bentonite. Humectants are present in the composition to aid in slowing the evaporation of the water present in the composition and some provide a solvent effect in removing grease. Exemplary of useful humectants are the glycols (glycerol, propylene glycol and polyethylene gylcol). Organic solvents are present in the composition to aid in the removal of grease from the oven surface. Exemplary of organic solvents are those which aid in grease removal and are not adversely affected by the other ingedients and do not pesent a fire hazard. These include tripropyleneglycol methyl ether, diethyleneglycol monobutyl ether. Foam stabilizers are present so that when the composition is applied as a foam from an aerosol unit, the resulting of the valve. The aerosol container unit consists of a pressure-tight aerosol container having a valve-controlled opening and containing a composition as set forth herein and from about 1.00% to about 25.00% of a propellant. Propellants are selected from the wcll known compatible propellants such as isobutane, isobutane/propane, dichlorodifluoromethane (Freon 12), trichlorofluoromethane (Freon 11), dichlorotetrafluoroethane (Freon 114) and 1,l,2-trichlorotrifluoroethane (Freon 113). The propellant should be effective at atmospheric temperature and not adversely react with any components of the composition. Additionally, the aerosol container may contain from about 0.10% to about 0.25% of wax pellets. The wax increases the adherence of the formula to the walls of the oven and is preferably added in pellet form by dissolving in the propellant. The waxes used are any of the readily available types such as beeswax, scale wax (crude) or parafiin waxes. These Waxes are solids at room temperature and soften in the range of 100 F. to 200 F.

The following examples are given by way of illustration and are not to be construed as limitations of this invention, many variations of which are possible without departing from the scope and spirit thereof.

EXAMPLE I In the table following, Group IFormulations, are indicated formulations numbered consecutively l-9-. These formulations are expressed in percent by weight and upon testing, using recognized methods, are excellent non-fumfoam will remain stable to preserve the opacity provided 0 8 Oven Cleaners of enhanced y- TABLE I.-GROUP I (FORMULATIONS) Amounts expressed as percent by weight Formulation Number 1 2 3 4 5 6 7 8 7 Water. 64. 71 74. 71 63. 71 65. 71 65. 62 64. 42 65. 42 66. 76 64. 79 Potassium nleate 0. 68 Potassium caprylate 0. 09 0. 09 0. 09 0. 09 0. 18 0. l8 0. 36 18 Potassium carbonate.-. 4. 00 4. 00

Tri potassium phosphate 10. 0 l0. 0 10. 0 10. 0 10. 0 10. 0 10, 0 2-[2-(8-aminopropoxy)ethoxy1ethanol 30. 0 20- 0 5- 00 3. 00 3. 00 3. 00 2. 00 0. 50 3. 00 Magnesium aluminum silicate (V eegum T) 1. 20 1- 0 1. 0 1. 20 1- 0 0. 90 0. 90 0. 90 0. 90 GlyceroL 20. 0 20. 0 10. 0 10. 0 10. 0 10. 0 10. 0 Tripropyleneglycol methyl ether (Dowanol 'IPM) 10- 0 1 0 10. 0 10. 0 10. 0 Diethanolamide ofeoconut fatty acids (Witcamide 272) 0. 50 0. 50 0. 46 0. 47 Silicaflnely divided (Cab-O-Sil M-5) 1. 00 1. 00 1. 01

by the soap. Exemplary of the foam stabilizers are the diethanolarnides of coconut fatty acids. The abrasives are added to provide additional cleaning power to aid in removing stubborn stains; additionally, certain abrasives serve to increase viscosity and to absorb the emulsifier and propellant in pressurized aerosol systems, providing a superior product. Exemplary of abrasives producing all the above properties is a silica such as Cab-O-Sil M5 or Aerosil 200. A selection of the above-described optional ingredients provides a composition with many desirable attributes; i.e. such as an aerosol composition which is opaque for an extended period providing visual evidence of where it has been applied.

The herein disclosed compositions are useful in cleaning ovens when applied to cold (ambient room temperature) or hot (up to 300 F.) soiled ovens and allowed to remain on the soiled surfaces until the grime is softened, followed by wiping away the composition, preferably with a damp cloth or sponge. Extremely hot temperatures impede cleaning action due to the fast evaporation of the water present in the composition. However, the most efficient method of using the disclosed compositions is to apply them to an oven preheated (200 R), which is maintained at that temperature during the entire cleaning procedure (i.e. not turned off). The composition is allowed to remain on the heated oven surfaces for about ten to about thirty minutes, depending on degree of soiling, followed by removal with a damp cloth or sponge.

In the preferred form, the oven cleaning compositions are supplied in self-contained valve-controlled aerosol units which provide a fine spray or foam upon activation In Table I, formulations one and two demonstrate the use of high levels of enchancing agents in a single formulation. Formulations theree, four and five use low levels of enhancer and additionally contain glycerol as a humectant and magnesium aluminum silicate for thickening. Formulations six and seven also include an alkanolamide of coconut fatty acids to stabilize the foam and finely divided silica to absorb the propellant and increase foam efiects. Formulation eight is an opaque foam product using a low concentration of the enhancing agent. Formulation nine is an extremely opaque spray composition formulation and is visible immediately to the user upon spraying.

EXAMPLE H The compositions of Example I are provided using as an enhancer 2-(2-[2-(3-aminopropoxy)ethoxy]ethoxy) ethanol.

EXAMPLE m Aerosol systems are provided using the compositions of Example I (base concentrate) and a propellant and optionally wax. Each provided excellent use characteristics in the cleaning of dirty ovens.

What is claimed:

1. A non-caustic alkali, water-based oven cleaner composition consisting essentially of water, about .05 to about 1% by weight of a soap comprising a salt of at least one fatty acid; from about 4 to about by weight of an inorganic cleaner selected from the class consisting of a carbonate, a phosphate, a borate and a silicate whose cationic portion is selected from the class consisting, of an alkali metal and ammonium; and from about 0.5 to about 30% by weight of an enhancing agent of the formula:

wherein n is a number from about 2 to about 12.

2. The composition of claim 1 wherein said soap is selected from the group consisting of potassium oleate and potassium caprylate.

3. The composition of claim 1 wherein said inorganic cleaner is selected from the group consisting of potassium carbonate and tripotassium phosphate.

4. The composition of claim 1 wherein said enhancing agent is present in the amount of 0.50% to about 5.00%.

5. A package consisting of a pressure-tight aerosol container having a valve-controlled opening and a composition for use in cleaning ovens and similar surfaces said composition consisting of from about 1.00% to about 25 .00% propellant, with the remainder being the composition of claim 1.

6. A package consisting of a pressure-tight aerosol container having a valve-controlled opening and a composition for use in cleaning ovens and similar surfaces said composition consisting of from about 1.00% to about 25.00% propellant, with the remainder being the composition of claim 1.

7. The composition of claim 1 which additionally contains from about 0.10% to about 0.25% of wax pellets which are solids at room temperature and soften in the range of about F. to 200 F.

8. The composition according to claim 1 wherein said enhancing agent is 2-[2(3-aminopropoxy)ethoxy] etha- 1101.

References Cited UNITED STATES PATENTS 3,296,147 1/1967 Gatza 252153 2,786,080 3/1957 Patton 260584 B 3,022,335 2/ 1962 'Lnndsted 252-153 3,161,682 12/ 1964 'Lesesne et al 260548 B 3,001,947 9/1961 Stahler et al. 252-153 3,198,747 8/1965 Cook et al 252--156 LEON D. ROSDOL, Primary Examiner W. E. SCHULZ, Assistant Examiner US. Cl. X.R. 252-453, 156

3 UNITED STATES PATENT OFFICE CERTIFICATE OF CORRECTION Patent No. 3, 5 ,7 Dated September 12, 1972 Inventor(s) Cromwell D. Mukai and Frank L. Steckhahn It is certified that error appears in the above-identified patent' and that said Letters Patent are hereby corrected as shown below:

-' Column 2, line 14, change "over" to --oven--.

Column 3, line 26, change "pesent" to --present-- 7 Column 4, line IT, change "theree" to --three--.

Table I (bridging columns 3 and 4 of the patent%, under Formulation No. line 1, change "66.76" to 6.67--.

Table I, under Formulation No 8, line 2, change "CAD" to Table I, last column, line 1, change "64.79 to --6 L.77--.

Table I, last column, change formulation No. "7". to --9--.

Signed and sealed this 20th day of March 1973.

(SEAL) Attes t EDWARD M FLETCHER JR ROBERT GOTTSCHALK Attesting Officer Commissioner of Patents 

